Ultrafine Polyester Fiber Structure for Uniform Diameter Dispersion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing technologies face challenges in achieving uniform fiber diameter and dispersibility regardless of aspect ratio, leading to issues with surface smoothness in wet-laid nonwoven fabrics produced using ultrafine polyester fibers.
Innovation Solution
The ultrafine polyester fibers are engineered to have precise control over cross-sectional area, standard deviation, and roundness, with specific ratios and variations, ensuring improved dispersibility and surface smoothness by minimizing outliers in cross-sectional areas and maintaining a circular shape.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If ultrafine fibers are produced by removing sea component from sea-island composite fiber, then fiber fineness is improved, but fiber diameter uniformity deteriorates due to unstable flow and merging of island components
Solution Approach 1:
The invention extracts and removes the sea component (polyester resin) from the sea-island composite fiber structure, leaving only the ultrafine island components (cellulose acetate) to form the final ultrafine fiber. This extraction process achieves the desired fiber fineness while the controlled removal prevents the merging issues that occur when trying to maintain uniform island distribution
Solution Approach 2:
Instead of trying to create uniform ultrafine fibers directly through conventional spinning methods, the invention inverts the approach by first creating a sea-island composite fiber with controlled domain distribution, then removing the sea component to reveal the ultrafine island components. This inverted process achieves better diameter uniformity than direct ultrafine fiber formation
2Length of moving object
If fiber aspect ratio is increased to improve flexibility, then fiber length increases, but dispersibility deteriorates due to increased intermingling of fibers
Solution Approach 1:
The invention changes the critical parameter of fiber cross-sectional area (keeping it small at 1-40 μm²) while allowing fiber length to vary, thereby achieving high aspect ratios without sacrificing dispersibility. The small cross-sectional area prevents excessive intermingling even when fibers are long
3Volume of moving object
If fiber cross-sectional area is reduced to achieve ultrafine fibers, then fiber fineness is improved, but surface smoothness of wet-laid nonwoven fabric deteriorates due to increased variation in cross-sectional dimensions
Solution Approach 1:
The invention performs preliminary control of the island component domain size and distribution during the sea-island composite fiber formation stage, ensuring that when the sea component is removed, the remaining ultrafine fibers have uniformly small cross-sectional areas. This preliminary action prevents excessive variation in final fiber dimensions
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The engineered fibers exhibit excellent dispersibility and produce wet-laid nonwoven fabrics with enhanced surface smoothness, improving the quality of paper-like materials.
Implementation Method 1
a spinning step of melt-spinning a resin material containing a polyester-based resin
Implementation Method 2
a drawing step of drawing the fiber obtained in the spinning step
Data Source
AI summary
Provided is an ultrafine polyester fiber capable of exhibiting excellent dispersibility regardless of an aspect ratio. The polyester fiber may have an average cross-sectional area x of 1 to 40 µm2, a standard deviation σ of a cross-sectional area of 10 µm2 or less, a standard deviation σ of a cross-sectional area of 10 µm2 or less, and a ratio Ao/Ai of a sum Ao of cross-sectional areas of data outside a range of x ± 2.5σ to a sum Ai of cross-sectional areas of data within the range of x ± 2.5σ of 10% or less, wherein these values are calculated from data of cross-sectional areas of single fibers. The polyester fiber may have an average fiber diameter of single fibers of 1 to 10 µm, and a roundness of a fiber cross-section of 0.90 to 1.00.